Patents by Inventor Daniel Calafut

Daniel Calafut has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20120319197
    Abstract: In accordance with an embodiment a structure can include a monolithically integrated trench field-effect transistor (FET) and Schottky diode. The structure can include a first gate trench extending into a semiconductor region, a second gate trench extending into the semiconductor region, and a source region flanking a side of the first gate trench. The source region can have a substantially triangular shape, and a contact opening extending into the semiconductor region between the first gate trench and the second gate trench. The structure can include a conductor layer disposed in the contact opening to electrically contact the source region along at least a portion of a slanted sidewall of the source region, and the semiconductor region along a bottom portion of the contact opening. The conductor layer can form a Schottky contact with the semiconductor region.
    Type: Application
    Filed: August 30, 2012
    Publication date: December 20, 2012
    Inventors: Christopher Boguslaw Kocon, Steven Sapp, Paul Thorup, Dean Probst, Robert Herrick, Becky Losee, Hamza Yilmaz, Christopher Lawrence Rexer, Daniel Calafut
  • Publication number: 20120193748
    Abstract: Exemplary power semiconductor devices with features providing increased breakdown voltage and other benefits are disclosed.
    Type: Application
    Filed: April 11, 2012
    Publication date: August 2, 2012
    Inventors: Joseph A. Yedinak, Daniel Calafut, Dean E. Probst
  • Publication number: 20120156845
    Abstract: A method for forming a field effect transistor and Schottky diode includes forming a well region in a first portion of a silicon region where the field effect transistor is to be formed but not in a second portion of the silicon region where the Schottky diode is to be formed. Gate trenches are formed extending into the silicon region. A recessed gate is formed in each gate trench. A dielectric cap is formed over each recessed gate. Exposed surfaces of the well region are recessed to form a recess between every two adjacent trenches. Without masking any portion of the active area, a zero-degree blanket implant is performed to form a heavy body region of the second conductivity type in the well region between every two adjacent trenches.
    Type: Application
    Filed: December 13, 2011
    Publication date: June 21, 2012
    Applicant: Fairchild Semiconductor Corporation
    Inventors: Christopher Boguslaw Kocon, Steven Sapp, Paul Thorup, Dean Probst, Robert Herrick, Becky Losee, Hamza Yilmaz, Christopher Lawrence Rexer, Daniel Calafut
  • Patent number: 8193581
    Abstract: Exemplary power semiconductor devices with features providing increased breakdown voltage and other benefits are disclosed.
    Type: Grant
    Filed: April 8, 2009
    Date of Patent: June 5, 2012
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Joseph A. Yedinak, Dean E. Probst, Ashok Challa, Daniel Calafut
  • Patent number: 8174067
    Abstract: Exemplary power semiconductor devices with features providing increased breakdown voltage and other benefits are disclosed.
    Type: Grant
    Filed: April 2, 2009
    Date of Patent: May 8, 2012
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Joseph A. Yedinak, Daniel Calafut, Dean E. Probst
  • Publication number: 20120104490
    Abstract: A field effect transistor includes a body region of a first conductivity type over a semiconductor region of a second conductivity type. A gate trench extends through the body region and terminates within the semiconductor region. At least one conductive shield electrode is disposed in the gate trench. A gate electrode is disposed in the gate trench over but insulated from the at least one conductive shield electrode. A shield dielectric layer insulates the at lease one conductive shield electrode from the semiconductor region. A gate dielectric layer insulates the gate electrode from the body region. The shield dielectric layer is formed such that it flares out and extends directly under the body region.
    Type: Application
    Filed: October 21, 2011
    Publication date: May 3, 2012
    Inventors: Hamza Yilmaz, Daniel Calafut, Christopher Boguslaw Kocon, Steven P. Sapp, Dean E. Probst, Nathan L. Kraft, Thomas E. Grebs, Rodney S. Ridley, Gary M. Dolny, Bruce D. Marchant, Joseph A. Yedinak
  • Publication number: 20110303975
    Abstract: A field effect transistor includes a plurality of trenches extending into a semiconductor region of a first conductivity type. The plurality of trenches includes a plurality of gated trenches and a plurality of non-gated trenches. A body region of a second conductivity extends in the semiconductor region between adjacent trenches. A dielectric material fills a bottom portion of each of the gated and non-gated trenches. A gate electrode is disposed in each gated trench. A conductive material of the second conductivity type is disposed in each non-gated trench such that the conductive material and contacts corresponding body regions along sidewalls of the non-gated trench.
    Type: Application
    Filed: June 2, 2011
    Publication date: December 15, 2011
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Patent number: 8063442
    Abstract: A field effect transistor includes an active region and a termination region surrounding the active region. A resistive element is coupled to the termination region, wherein upon occurrence of avalanche breakdown in the termination region an avalanche current starts to flow in the termination region, and the resistive element is configured to induce a portion of the avalanche current to flow through the termination region and a remaining portion of the avalanche current to flow through the active region.
    Type: Grant
    Filed: December 30, 2010
    Date of Patent: November 22, 2011
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Hamza Yilmaz, Daniel Calafut
  • Patent number: 8043913
    Abstract: A method of forming a field effect transistor includes: forming a trench in a semiconductor region; forming a shield electrode in the trench; performing an angled sidewall implant of impurities of the first conductivity type to form a channel enhancement region adjacent the trench; forming a body region of a second conductivity type in the semiconductor region; and forming a source region of the first conductivity type in the body region, the source region and an interface between the body region and the semiconductor region defining a channel region therebetween, the channel region extending along the trench sidewall. The channel enhancement region partially extends into a lower portion of the channel region to thereby reduce a resistance of the channel region.
    Type: Grant
    Filed: March 29, 2011
    Date of Patent: October 25, 2011
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Hamza Yilmaz, Daniel Calafut, Christopher Boguslaw Kocon, Steven P. Sapp, Dean E. Probst, Nathan L. Kraft, Thomas E. Grebs, Rodney S. Ridley, Gary M. Dolny, Bruce D. Marchant, Joseph A. Yedinak
  • Publication number: 20110177662
    Abstract: A method of forming a field effect transistor includes: forming a trench in a semiconductor region; forming a shield electrode in the trench; performing an angled sidewall implant of impurities of the first conductivity type to form a channel enhancement region adjacent the trench; forming a body region of a second conductivity type in the semiconductor region; and forming a source region of the first conductivity type in the body region, the source region and an interface between the body region and the semiconductor region defining a channel region therebetween, the channel region extending along the trench sidewall. The channel enhancement region partially extends into a lower portion of the channel region to thereby reduce a resistance of the channel region.
    Type: Application
    Filed: March 29, 2011
    Publication date: July 21, 2011
    Inventors: Hamza Yilmaz, Daniel Calafut, Christopher Boguslaw Kocon, Steven P. Sapp, Dean E. Probst, Nathan L. Kraft, Thomas E. Grebs, Rodney S. Ridley, Gary M. Dolny, Bruce D. Marchant, Joseph A. Yedinak
  • Publication number: 20110089488
    Abstract: A field effect transistor includes an active region and a termination region surrounding the active region. A resistive element is coupled to the termination region, wherein upon occurrence of avalanche breakdown in the termination region an avalanche current starts to flow in the termination region, and the resistive element is configured to induce a portion of the avalanche current to flow through the termination region and a remaining portion of the avalanche current to flow through the active region.
    Type: Application
    Filed: December 30, 2010
    Publication date: April 21, 2011
    Inventors: Hamza Yilmaz, Daniel Calafut
  • Patent number: 7923776
    Abstract: A field effect transistor includes a body region of a first conductivity type in a semiconductor region of a second conductivity type. A gate trench extends through the body region and terminating within the semiconductor region. A source region of the second conductivity type extends in the body region adjacent the gate trench. The source region and an interface between the body region and the semiconductor region define a channel region therebetween which extends along the gate trench sidewall. A channel enhancement region of the second conductivity type is formed adjacent the gate trench. The channel enhancement region partially extends into a lower portion of the channel region to thereby reduce a resistance of the channel region.
    Type: Grant
    Filed: February 2, 2010
    Date of Patent: April 12, 2011
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Hamza Yilmaz, Daniel Calafut, Christopher Boguslaw Kocon, Steven P. Sapp, Dean E. Probst, Nathan L. Kraft, Thomas E. Grebs, Rodney S. Ridley, Gary M. Dolny, Bruce D. Marchant, Joseph A. Yedinak
  • Patent number: 7863708
    Abstract: A field effect transistor (FET) includes a source electrode for receiving an externally-provided source voltage. The FET further includes an active region and a termination region surrounding the active region. A resistive element is coupled to the termination region, wherein upon occurrence of avalanche breakdown in the termination region an avalanche current starts to flow in the termination region, and the resistive element is configured to induce a portion of the avalanche current to flow through the termination region and a remaining portion of the avalanche current to flow through the active region. During operation, one end of the resistive element is biased to the source voltage.
    Type: Grant
    Filed: April 16, 2009
    Date of Patent: January 4, 2011
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Hamza Yilmaz, Daniel Calafut
  • Publication number: 20100258862
    Abstract: A field effect transistor includes a body region of a first conductivity type in a semiconductor region of a second conductivity type. A gate trench extends through the body region and terminating within the semiconductor region. A source region of the second conductivity type extends in the body region adjacent the gate trench. The source region and an interface between the body region and the semiconductor region define a channel region therebetween which extends along the gate trench sidewall. A channel enhancement region of the second conductivity type is formed adjacent the gate trench. The channel enhancement region partially extends into a lower portion of the channel region to thereby reduce a resistance of the channel region.
    Type: Application
    Filed: February 2, 2010
    Publication date: October 14, 2010
    Inventors: Hamza Yilmaz, Daniel Calafut, Christopher Boguslaw Kocon, Steven P. Sapp, Dean E. Probst, Nathan L. Kraft, Thomas E. Grebs, Rodney S. Ridley, Gary M. Dolny, Bruce D. Marchant, Joseph A. Yedinak
  • Publication number: 20100258855
    Abstract: A field effect transistor includes a plurality of trenches extending into a semiconductor region of a first conductivity type. The plurality of trenches include a plurality of gated trenches and a plurality of non-gated trenches. A body region of a second conductivity extends in the semiconductor region between adjacent trenches. A dielectric material fills a bottom portion of each of the gated and non-gated trenches. A gate electrode is disposed in each gated trench. A conductive material of the second conductivity type is disposed in each non-gated trench such that the conductive material and contacts corresponding body regions along sidewalls of the non-gated trench.
    Type: Application
    Filed: June 23, 2010
    Publication date: October 14, 2010
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Patent number: 7767524
    Abstract: A method of forming a charge balance MOSFET includes the following steps. A substrate with an overlying epitaxial layer both of a first conductivity type, are provided. A gate trench extending through the epitaxial layer and terminating within the substrate is formed. A shield dielectric lining sidewalls and bottom surface of the gate trench is formed. A shield electrode is formed in the gate trench. A gate dielectric layer is formed along upper sidewalls of the gate trench. A gate electrode is formed in the gate trench such that the gate electrode extends over but is insulated from the shield electrode. A deep dimple extending through the epitaxial layer and terminating within the substrate is formed such that the deep dimple is laterally spaced from the gate trench. The deep dimple is filled with silicon material of the second conductivity type.
    Type: Grant
    Filed: October 20, 2009
    Date of Patent: August 3, 2010
    Assignee: Fairchild Semiconductor Corporatiion
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Publication number: 20100140696
    Abstract: Exemplary power semiconductor devices with features providing increased breakdown voltage and other benefits are disclosed.
    Type: Application
    Filed: April 2, 2009
    Publication date: June 10, 2010
    Inventors: Joseph A. Yedinak, Daniel Calafut, Dean E. Probst
  • Publication number: 20100140697
    Abstract: Exemplary power semiconductor devices with features providing increased breakdown voltage and other benefits are disclosed.
    Type: Application
    Filed: April 8, 2009
    Publication date: June 10, 2010
    Inventors: Joseph A. Yedinak, Dean E. Probst, Ashok Challa, Daniel Calafut
  • Publication number: 20100038708
    Abstract: A method of forming a charge balance MOSFET includes the following steps. A substrate with an overlying epitaxial layer both of a first conductivity type, are provided. A gate trench extending through the epitaxial layer and terminating within the substrate is formed. A shield dielectric lining sidewalls and bottom surface of the gate trench is formed. A shield electrode is formed in the gate trench. A gate dielectric layer is formed along upper sidewalls of the gate trench. A gate electrode is formed in the gate trench such that the gate electrode extends over but is insulated from the shield electrode. A deep dimple extending through the epitaxial layer and terminating within the substrate is formed such that the deep dimple is laterally spaced from the gate trench. The deep dimple is filled with silicon material of the second conductivity type.
    Type: Application
    Filed: October 20, 2009
    Publication date: February 18, 2010
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Patent number: 7625799
    Abstract: A semiconductor region with an epitaxial layer extending over the semiconductor region is provided. A first silicon etch is performed to form an upper trench portion extending into and terminating within the epitaxial layer. A protective material is formed extending along sidewalls of the upper trench portion and over mesa regions adjacent the upper trench portion but not along a bottom surface of the upper trench portion. A second silicon etch is performed to form a lower trench portion extending from the bottom surface of the upper trench portion through the epitaxial layer and terminating within the semiconductor region, such that the lower trench portion is narrower than the upper trench portion.
    Type: Grant
    Filed: April 6, 2009
    Date of Patent: December 1, 2009
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa